I imagine a single state-owned database where merchants enter detailed product information. The consumers may then query the database at their leisure.
I'd trust the UK civil service to do that. The hardest but would probably be verification -- does that lasagne really only have beef in, was the cocoa for that chocolate actually grown in a Fairtrade farm, in Ivory Coast, etc..
I'm American. I don't even trust my government to do math properly.
The French, bring back Le Minitel!
And if there is a change in the political spectrum, will you still trust them? My government lost my security clearance application to who knows who. In return, I got some credit monitoring and a form letter.
India has something similar. Datakart app from gs1 has product related information. You can scan using barcodes.